Problem: Evaluate the following expression when $x = 2$ and $y = 1$. $8$ $x$ $ + 3$ $y$ $ + 6$
Solution: Substitute $2$ for ${x}$ and $1$ for ${y}$ $ = 8{(2)} + 3{(1)} + 6 $ $ = 16 + 3 + 6 $ $ = 25$